Newcomer

Veteran

Most modern appliances (computers, phones, hair dryers etc...) work both on 110 and 220... their should be something written on your charger, or on the back/somewhere on the appliance... An adapter from 110 to 220..or the other way around..(the actual plug configuration) cost about 4 pesos here...That being said.. all the items brought with me were for phone, camera. lap-top and razor chargers...If you are talking about major appliances (dish washer, oven, plazma etc...) not sure... but "transformers" are quite a simple device... (really just a bundle of wires to absorb a bit of the extra zzzzz ) witch I am sure they produce localy in Argentina... most likely not too expensive...

Veteran

Depends on what you are trying to do. You can get a coverter which is really for things like razors, etc. you only use once a day. If you have say a tv or some other major appliance you need to get a transformer which you can buy in Argentina. Transformers are sized in watts. To calculate the watts of a particular appliance the formula is Amps x voltage = watts(i.e. an appliance that takes 5 amps would need approximately a 600 watt transformer 5 amps X 110 volts = 550 watts).
You can buy individual transformers for each appliance or buy one big one and have your house or apartment wired to run 110. I did that once there as I had a bunch of stuff from the states. You just need to make sure you know which outlets are 110 versus 220 if you do this.